In the field of chemical analyzers, there is a need to enhance the throughput, particularly at large user sites such as large hospitals. When using dried slides as the test elements, for example, the "Electachem".RTM. slides available from the Clinical Diagnostics Division of Eastman Kodak Company, a limiting factor in increasing the throughput is the speed at which the aspirator can aspirate and dispense patient sample onto the slide test elements. This speed in turn is affected by the need for the aspirator to repeatedly eject the disposable tip previously used, and pick up a new one, each time a different patient sample is to be tested. Such a mechanical operation is time consuming.
One solution to the time needed to eject and pick up a new disposable tip is to use more than one aspirator at the metering station. However, one of the difficulties in doing this is that multiple aspirators require a multiple of supplies of tips. No arrangement has been available for tripling or quadrupling the supply for a triplet or quartet aspirator, without unduly burdening operators with an impossible task of manual loading thousand of tips per hour in an ordered array.
An alternative is to supply tips in a rack that is sampled automatically. This solves the problem of operator labor but adds significant cost to the tips. In addition, the rack then must be disposed, adding to the laboratory cost of waste management as well as negatively impacting the environment.
Hence, prior to this invention there has been a need for a mechanism and method that will somehow supply an array of tips to a multiple aspirator system in an analyzer, without requiring separate hand-placement of each and every tip in the array and without requiring the disposal of empty tip racks.